document.write( "Question 565327: On a recent trip Sarah's car traveled 20 mph faster on the first 150 miles than it did on the remaining 80 miles. The total time for the trip was 4 hours. Find the speed of the first part of the trip and show work. \n" ); document.write( "
Algebra.Com's Answer #365754 by mananth(16946)\"\" \"About 
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Second part x x mph 80 miles
\n" ); document.write( "First part x+ 20 mph 150 miles
\n" ); document.write( "Time first part +Time second part = 4 hours
\n" ); document.write( "150 / (x 20 )+ 80 /x= 4
\n" ); document.write( "Multiply equation by the LCD (x+ 20 )x
\n" ); document.write( "150 x+ 80 (x+ 20 )= 4
\n" ); document.write( "150 x+ 80 x+ 1600 = 4 (x+ 20 )*x
\n" ); document.write( "150 x+ 80 x+ 1600 = 4 X^2 + 80 x
\n" ); document.write( "4 X^2 -150 x -1600 = 0
\n" ); document.write( "Find the roots of the equation by quadratic formula
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\n" ); document.write( "a= 4 , b= -150 , c= -1600
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\n" ); document.write( "b^2-4ac= 22500 + 25600
\n" ); document.write( "b^2-4ac= 48100 \"%09sqrt%28%0948100%09%29=%09219.32%09\"
\n" ); document.write( "\"x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29\"
\n" ); document.write( "\"x1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29\"
\n" ); document.write( "x1=( 150 + 219.32 )/ 8
\n" ); document.write( "x1= 46.16
\n" ); document.write( "x2=( 150 -219.32 ) / 8
\n" ); document.write( "x2= -8.66
\n" ); document.write( "Ignore negative value
\n" ); document.write( "= 46.16 mph speed in second part\r
\n" ); document.write( "\n" ); document.write( "66.16 mph in first part
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\n" ); document.write( "m.ananth@hotmail.ca
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